Autoimmune pancreatitis:extrapancreatic imaging findings

目的:分析自身免疫性胰腺炎(AIP)胰外病变的影像特点,提高对AIP认识和诊断水平.方法:搜集17例AIP患者的CT和/或MR资料,分析总结胰周假包膜形成,血管受累,胆道扩张,腹膜后纤维化及远处器官侵犯等胰外病变的影像学表现.结果:17例AIP中10例伴胰周假包膜形成,假包膜的部位、形态呈多样性；5例伴脾动脉和/或脾静脉受累；5例伴胆管扩张,其中1例伴节段性胆管壁增厚、管腔狭窄；2例伴肾侵犯,1例伴肠系膜侵犯,肾内和肠系膜病变均呈结节状较高软组织密度,质地均匀,进行性均匀强化；1例伴腹膜后纤维化,纤维组织质地均匀度、强化特点与肾内及肠系膜病变相同.结论:胰周假包膜对AIP诊断有肯定意义,其它胰外病变亦具有一定特征性.掌握AIP胰外病变的影像特征有利于该病的诊断与鉴别诊断,减少误诊.     

Autoimmune pancreatitis associated with primary sclerosing cholangitis: MR imaging findings

Autoimmune pancreatitis is a relatively rare type of chronic pancreatitis that may be associated with other autoimmune disorders. The imaging features of this entity may be misleading and suggest the presence of a malignant tumour. We present a case in which MR imaging allowed us to diagnose autoimmune pancreatitis associated with primary sclerosing cholangitis, which is another autoimmune-related disease. Typical MR characteristics of autoimmune pancreatitis include focal or diffuse enlargement of the pancreas, the absence of parenchymal atrophy and significant dilation proximal to the site of stenosis, the absence of peripancreatic spread, the clear demarcation of the lesion and the presence of a peripancreatic rim.     

自身免疫性胰腺炎1例

患者 男,69岁.因上腹饱胀不适伴排便习惯改变、消瘦2月,1周前出现全身皮肤黏膜黄染,大便颜色变浅,小便色黄,逐来我院入院检查.实验室检查:尿常规中白细胞25/ul,血常规正常,总胆红素103.7umol/L,直接胆红素22.7umol/L,总蛋白84g/L,球蛋白42g/L,白蛋白/球蛋白=1,丙氨酸氨基转移酶347U/L,门冬氨酸氨基转移酶136U/L,碱性磷酸酶246U/L,总胆汁酸13umol/L,γ-谷氨酰转肽酶604U/L,尿酸0.55umol/L,ESR 28mm/H,AFP、CEA正常,CA199 104.8U/mL;IgG4升高(26.20g/L),IgG升高(22.80g/L),IgE升高(153g/mL),补体C4下降(0.14g/L),血清蛋白电泳白蛋白下降(47.7％),α2球蛋白正常(8.7％),γ球蛋白升高(31.6％).     

Autoimmune pancreatitis: imaging findings on contrast-enhanced MR, MRCP and dynamic secretin-enhanced MRCP

Purpose

This study retrospectively determined magnetic resonance (MR), MR cholangiopancreatography (MRCP) and secretin-MRCP findings in patients with autoimmune pancreatitis (AIP).

Materials and methods

The MR examinations of 28 patients with histopathologically proven AIP were reviewed. In 14 cases, secretin-enhanced MRCP was performed. The observers evaluated pancreatic parenchymal enlargement, signal intensity abnormalities, enhancement, vascular involvement, bile-duct diameter and main pancreatic duct (MPD) narrowing (diffuse/focal/segmental). After secretin administration, the presence of the “duct-penetrating” sign was evaluated.

Results

MR imaging showed diffuse pancreatic enlargement in 8/28(29%) cases, focal pancreatic enlargement in 16/28 (57%) cases and no enlargement in 4/28 (14%) cases. The alteration of pancreatic signal intensity was diffuse in 8/28 (29%) cases (eight diffuse AIP) and focal in 20/28 (71%) cases (20 focal AIP). Delayed pancreatic enhancement was present in all AIP, with peripheral rim of enhancement in 8/28 (29%) AIP (1/8 diffuse, 7/20 focal); vascular encasement was present in 7/28 (25%) AIP (1/8 diffuse, 6/20 focal); distal common bile duct narrowing was present in 12/28(43%) AIP (5/8 diffuse, 7/20 focal). MRCP showed MPD narrowing in 17/28 (61%) AIP (4/8 diffuse, 15/20 focal), MPD dilation in 8/28(29%) AIP (3/8 diffuse, 5/20 focal) and normal MPD in1/8 diffuse AIP. Secretin-MRCP showed the duct-penetrating sign in 6/14(43%) AIP (one diffuse AIP with MPD segmental narrowing, five focal AIP with MPD focal narrowing), demonstrating integrity of the MPD.

Conclusions

Delayed enhancement and MPD stenosis are suggestive for AIP on MR and MRCP imaging. Secretin-enhanced MRCP is a problem-solving tool in the differential diagnosis between focal AIP and ductal adenocarcinoma.     

Chronic pancreatitis: ultrasonic features

A retrospective analysis of 84 ultrasound examinations (in 77 patients) was performed to assess the frequency of sonographic findings in chronic pancreatitis. The findings included: inhomogeneously increased echogenicity in 53% of these examinations, focal or diffuse enlargement in 41%, focal dense echoes in 40%, pseudocyst formation in 21%, and a hypoechoic head mass in 7%. Thirteen per cent of our patients had a normal sonogram. Several presentations of chronic pancreatitis not previously described in the sonographic literature included: pancreatic or common bile duct enlargement or pseudocyst formation with otherwise normal-appearing glands. There was no direct relationship between the presence of focal high-intensity echoes within the pancreatic parenchyma and the presence of radiographic calcification. There was no difference in the frequency of ultrasonic abnormalities between patients with and without clinical evidence of pancreatic insufficiency. These results indicate that the sonographic findings in chronic pancreatitis are significantly more varied than previous reports would indicate.     

Autoimmune pancreatitis with multifocal mass lesions

Autoimmune pancreatitis (AIP) is radiologically characterized as diffuse swelling of the pancreatic parenchyma and irregular narrowing of the pancreatic ducts. We present a case of AIP with multiple small nodular lesions in the pancreas. This case suggests that AIP with only small nodular or localized lesions is more difficult to differentiate from pancreatic cancer than typical cases of AIP.     

Pancreatic islet cell tumours presenting as recurrent acute pancreatitis: imaging features in three cases

We present three cases of recurrent pancreatitis that occurred in patients with small islet cell tumours of the pancreas which were obstructing the main pancreatic duct. This is a very uncommon presentation of pancreatic islet cell tumours. The radiological findings in these cases are shown and the implications for imaging of 'idiopathic' relapsing pancreatitis are discussed.     

Elastofibroma: imaging features

Elastofibroma dorsi is a rare benign and slow growing fibro-proliferative lesion of unknown pathogenesis. It has a characteristic location (periscapular region) and a specific imaging appearance (songraphy, CT, MRI) allowing accurate prospective diagnosis. The recognition of this benign lesion avoids unnecessary biopsy and/or surgery. We report three cases of elastofibroma dorsi illustrating the characteristic features on sonography, CT and MRI. Involvement was bilateral in two cases.     

自身免疫性胰腺炎的MR诊断与鉴别诊断

目的分析自身免疫性胰腺炎的MRI表现,旨在提高对其诊断的准确率。方法对经临床证实的10例自身免疫性胰腺炎进行回顾性分析,10例均行MR平扫及增强扫描检查。结果胰腺弥漫性受累(8/10),胰头局限性肿块(1/10),胰体尾部受累(1/10);6例可见"假包膜"征。MRCP:9例胆总管胰腺段狭窄,8例见胰管局限性或弥漫性狭窄,1例主胰管未见显示;动态增强后病变区呈延迟性强化。结论 MRI表现有一定的特点,需要和其它胰腺病变进行鉴别诊断,从而做出正确的诊断。     

自身免疫性胰腺炎（附5例报告）

目的：分析自身免疫性胰腺炎（autoimmune pancreatitis,AIP）患者的影像学表现、临床特征、血清学检查及病理学结果。方法：从2004年12月-2008年11月,回顾分析了5例AIP病例,其中3男2女,平均年龄为58．2岁（范围：54～65岁）。诊断标准符合Kim标准及修订的日本标准。结果：5名AIP患者的临床表现包括：黄疸（5／5）、腹痛（2／5）及糖尿病（3／5）。实验室检查：2名患者血沉增快;3名患者IgG水平升高;4名患者CA19．9升高。CT表现：胰腺弥漫肿大（4／5）或胰头肿块（1／5）;MRCP表现：胆总管下段狭窄（5／5）;ERCP表现：主胰管弥漫性狭窄和胆总管局限性狭窄。4名患者因怀疑胰腺癌而进行了开腹探查手术,此4名患者的病理表现为AIP特征性的胰腺淋巴浆细胞浸润及纤维化。2名患者接受了糖皮质激素治疗,胰腺肿大减轻。其中1名患者在激素减量过程中复发,再次给予激素治疗后2次好转。结论：AIP的影像学表现具有一定特征性。综合分析其影像学表现、临床症状、血清学检查及对激素治疗的反应等因素可以对AIP作出早期正确诊断,以避免不必要的开腹手术。     

CT成像的放射组学特征在胰腺炎诊断中的评估效能

目的 探讨胰腺CT成像的放射组学特征在功能性腹痛（FAP）、复发性急性胰腺炎（RAP）、慢性胰腺炎（CP）患者诊断中的评估效能。 方法 回顾性分析2017年12月至2020年12月在首都医科大学附属北京天坛医院接受腹部增强CT检查的168例患者的CT影像资料,根据纳排标准,共选取48例患者进行研究,其中男性 23例、女性25例,年龄39~84（47.8±10.2）岁;FAP患者16例（FAP组）、RAP患者18例（RAP组）、CP患者14例（CP组）。通过在CT图像上绘制感兴趣区来勾画胰腺轮廓。从每个感兴趣区提取62个放射组学特征,共分为5类,分别是一阶统计量、灰度共生矩阵（GLCM）、灰度行程矩阵（GLRLM）、邻域灰度差矩阵（NGTDM）和形态学特征,并在3组患者间进行比较。根据组别建立3个IsoSVM机器学习模型,对IsoSVM模型进行训练,并在遗漏的交叉验证样本上进行测试。RAP患者、FAP患者、CP患者的放射组学特征的比较采用Wilcoxon秩和检验。使用受试者工作特征曲线及曲线下面积（AUC）评估个体放射组学特征的评估效能。 结果 在单变量分析中,9个放射组学特征（8个GLCM特征和1个NGTDM特征）在患者组间的差异有统计学意义（Z=3.45~29.76,均P<0.05）。RAP患者与FAP和CP患者分别进行比较,放射组学特征的AUC范围分别为0.76~0.93和0.73~0.91。IsoSVM机器学习模型的总体预测准确率为82.1%。FAP组的灵敏度、特异度分别为78.7%、100%,AUC为0.90。RAP组的灵敏度、特异度分别为95.2%、77.8%,AUC为 0.87,而CP组的灵敏度、特异度分别为70.9%、94.8%,AUC 为0.89。 结论 CT成像的部分放射组学特征对胰腺炎的诊断有较好的评估效能,可以区分FAP、RAP和CP患者。     

Abdominal tuberculosis: imaging features

Radiological findings of abdominal tuberculosis can mimic those of many different diseases. A high level of suspicion is required, especially in high-risk population. In this article, we will describe barium studies, ultrasound (US) and computed tomography (CT) findings of abdominal tuberculosis (TB), with emphasis in the latest. We will illustrate CT findings that can help in the diagnosis of abdominal tuberculosis and describe imaging features that differentiate it from other inflammatory and neoplastic diseases, particularly lymphoma and Crohn's disease. As tuberculosis can affect any organ in the abdomen, emphasis is placed to ileocecal involvement, lymphadenopathy, peritonitis and solid organ disease (liver, spleen and pancreas). A positive culture or hystologic analysis of biopsy is still required in many patients for definitive diagnosis. Learning objectives:     

Pancreatic mass due to chronic pancreatitis: correlation of CT and MR imaging features with pathologic findings.

OBJECTIVE: The purpose of this study was to identify helical CT and MR imaging features of pancreatic masses (focal enlargement) due to chronic pancreatitis and their correlation with pathologic findings. CONCLUSION: When histologic fibrosis is uniformly present through the pancreas in patients with chronic pancreatitis, there is no demarcation of masses due to chronic pancreatitis. When there is a greater degree of histologic fibrosis in the masslike part of the pancreas, the mass is often demarcated from the remaining pancreas, and the enhancement pattern on two-phase helical CT and dynamic gadolinium-enhanced MR imaging mimics that of pancreatic adenocarcinoma.     

Autoimmune prostatitis with autoimmune pancreatitis: A case report and review of literature

Autoimmune pancreatitis is a type of chronic pancreatitis characterized by an inflammatory process with lymphoplasmacytic infiltration associated with fibrosis of the pancreas. Various autoimmune extrapancreatic manifestations are associated with this condition which includes biliary pathologies like sclerosing cholangitis, inflammatory bowel disease, sialadenitis, renal and pulmonary lesions and retroperitoneal fibrosis. Autoimmune prostatitis is rarely associated with autoimmune pancreatitis with only a handful number of cases reported so far. Imaging plays a role in differentiating this entity from prostatic cancer and documenting the response to therapy. Increased uptake within the prostate has been described on FDG-PET imaging in cases of autoimmune pancreatitis. However, ultrasound and MRI findings of this entity have not been reported. Hereby, we report a case of autoimmune prostatitis with autoimmune pancreatitis, present ultrasound findings and review the relevant literature.     

CT连续容积检查测定肾肿瘤生长速率的分布

目的 通过在CT连续容积检查上测定肿瘤大小和最大直径，回顾性研究不同大小、类型的肾皮质肿瘤的生长速率分布。方法 该回顾性研究符合HIPAA法案，获审查委员会批准。1989--2006年，2304例病人进行了肾脏切除术、术前化疗或放射治疗，其中53例[34例男性，19例女性，平均年龄（67±10）岁，范同39～88岁]病人术前接受了至少2次增强CT检查（间隔至少3个月），检查层厚相同，不超过1／5的纵向肿瘤直径。